Associations Of Total And Aerobic Steps With Health-related Quality Of Life In Older Adults

PURPOSE: Data on the associations of total daily steps with a health-related quality of life (HRQoL) in older adults are limited. We examined the associations of objectively measured total and aerobic (≥60 steps/min with ≥10 min continuous walking) steps with HRQoL in older adults. METHODS: This cross-sectional study included 831 older adults aged ≥65 years (59% female, mean age 72). HRQoL, including physical component summary (PCS) and mental component summary (MCS) scores, was evaluated using SF-36. PCS and MCS scores <50 were defined as low physical and mental HRQoL. Average daily steps over 7 days were assessed with tri-axial accelerometer-based pedometers. Participants were classified into tertiles of total steps/day (low, middle, and high) and 3 categories of aerobic steps/day (no [0 aerobic steps], low [lower 50%], and high [upper 50%]). Multivariable logistic regression was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) of low physical and mental HRQoL across the step categories after adjusting for age, sex, body mass index, smoking status, heavy alcohol drinking, education, marital status, and number of comorbidities (arthritis, hypertension, asthma, diabetes, cardiovascular disease, chronic kidney disease, chronic obstructive pulmonary disease, and cancer). RESULTS: There were 31 (4%) and 15 (2%) participants with low physical and mental HRQoL, respectively. Mean (SD) total daily steps and aerobic steps (among 594 participants [71%] with ≥1 aerobic steps) were 5,633 (3,171) and 2,262 (2,273), respectively. Compared to low total step or no aerobic step, the ORs (95% CIs) of low physical HRQoL were 0.31 (0.11, 0.89) and 0.07 (0.01, 0.59) in middle and high total steps, and 0.61 (0.25, 1.49) and 0.18 (0.04, 0.82) in low and high aerobic steps, respectively, after adjusting for the potential confounders. Corresponding results for low mental HRQoL were 0.46 (0.12, 1.71) and 0.10 (0.01, 0.83) in middle and high total step and 0.73 (0.22, 2.46) and 0.24 (0.04, 1.34) in low and high aerobic step. CONCLUSION: This study suggests that higher total and aerobic steps were associated with lower prevalences of low physical HRQoL, but only total steps were associated with a lower prevalence of low mental HRQoL in older adults. However, prospective studies are warranted.